| 摘要 |
1,097,865. Combine harvesters. TEXAS INDUSTRIES Inc. Feb. 3, 1965 [Feb. 12, 1964], No. 4781/65. Heading A1F. A tractor-mounted combine-harvester which is adapted automatically to maintain a substantially constant cutting height comprises support wheels (11) (Fig. 1, not shown) about which the harvester is pivotable and feeler members e.g. wheels 17 (Fig. 2) attached to and supporting a mowing platform 7A. The wheels 17 are mounted on arms 18 and their positions relative to the platform may be varied by means of hydraulically operable cylinders 21. Each feeler member has a corresponding lifting cylinder 51, and the operation of only one feeler member will be described. The platform is pivoted at 16A to portion 15, and upon relative movement a valve 40 in a hydraulic circuit is actuated by an arm 39 fixed to each crop divider 16. When the wheel 17 passes over a bump the ports 27, 29 of valve 40 are brought into communication to enable pump 33 (Fig. 3) to cause lifting cylinder 51 to be extended since a further valve 45 normally has its ports 27, 28 in communication. Similarly when the wheel 17 drops the ports 27, 28 of valve 40 are brought into communication and fluid in the cylinder 51 then flows to sump 31. Upon movement of lever 52 in direction M, the ports 27 of valve 45 are brought into communication and fluid passes from the pump directly to sump, thereby raising the platform. Movement of lever 37 controls actuation of cylinder 21. In another embodiment (Figs. 4 and 5, not shown) the feeler members comprise steel skids. |
